Bicycle



(No Model.) 4 Sheets-Sheet 1.

J. W. PROSSER. BICYCLE.

No. 507,081. Patented Oct. 17, 1893.

vwentoz (No Model.) 4 Sheets-Sheet 2.

J. W. PROSSER.-

BICYCLE.

No. 507,081. Patented Oct. 1'7, 1893.

(No Model.) 4Sheets-Sheet a.

' J. W. PROSSER;

BICYCLE. No. 507,081. Patented Oct. '17, 1893.

i iiiiiiiili r/ I lwMvw/aoao Y avvumtoz 3% i W WM (No Model.) 4 Sheets-Sheet 4.

J. W. PROSSER.

BIOYGLB. 7

No. 507,081. Patented Oct. 17,1893.

UNITED STATES PATENT OFFICE.

JOSEPH W. PROSSER, OF NEW LONDON, ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, TO CHARLES WATROUS AND STANISLAS D. BEAUSHENE,

OF LEDYARD, CONNECTICUT.

BICYCLE.

SPECIFICATION forming part of Letters Patent No. 507,081, dated October 17, 1893.

Application filed October '7, 1892. Serial No. 448,159. (No model.)

To all whom it may concern:

Be it known that I, JOSEPH W. PROSSER, a c tizen of the United States, residing in the city and county of New London and State of Connecticut, have invented certain new and useful Improvements in Bicycles, which improvements are fully set forth and described in the following specification, reference being had to the accompanying four sheets of drawto ings.

This invention relates particularly to the driving mechanism of cycles and has for its object the provision of simple differential gearln g and clutch mechanism controlling the I 5 same, whereby either high power or great speed may be attained. For ordinary use upon level or descending ground great speed 1s desirable rather than high power and at such times a simple system of sprocket gearng is provided substantially like that now 1n common use, but when it is desired to climb steep grades, speed is sacrificed to power and a system of gearing is brought into use by means of which the rider is able to imme- 2 5 diately bring to his aid powerful gearing, as

hereinafter described.

In the drawings hereto annexed Figure 1 is a side elevation of a complete bicycle contalnlng my newly invented driving mechan- 0 ism. Figs. 2 and 3 are, respectively, side and plan views of the differential gearing and attachments containing the essential features of said driving mechanism, the same being about one half of full size. Fig. 4 is a side View of said differential gearing showing the locking bolt 3O withdrawn to permit the smaller gear 24 to rotate independently of the internal gear 25 with which it meshes. Fig. 5 is a sectional view on line x-m of Fig. 0 4. Figs. 6, 7 and 8 illustrate said gearing in dlfferent positions, each being duly explained hereinafter. Figs. 10- and 11 are views of the bolt and its supporting arm employed to lock the smaller gear against rotation upon its shaft and Fig. 12 is a longitudinal sectional V ew of said bolt arm. Fig. 9 is a detached view of the crank-shaft of the cycle and Fig. 13 is a detached View of the body of a certain hook employed to coact with the bolt 3O 5c and its supporting arm.

Referring to the drawings, the figures 20 denote those portions of the frame of a socalled safety bicycle in which the crank shaft and sprocket wheel are ordinarily journaled and 21 denotes the said crank-shaft 5 5 having secured to eachend crank arms 22 with pedals 23 of any desired practical form. The middle portion of shaft Sl is formed as a double crank and upon the wristpin that connects the outer ends of the webs of said crank is loosely mounted a gear 24 that meshes with the teeth of an internal gear 25 loosely mounted upon shaft 21 between one of said webs and the adjacent frame 20 (see Fig. 5). The outer face or perimeter of said internal gear 25 is formed with sprocket teeth 26 adapted to. receive and drive a chain 27 that passes rearward around a sprocket wheel connected with the rear wheel of the bicycle in such manner that when rotary motion is given to the internal gear 25 the chain 27 will cause the rear cycle wheel to be correspondingly rotated.

Secured to the smaller gear 24 by screws 28 is an arm 29 upon which is mounted 5 to slide longitudinally a bolt 30 whose inner end, under certain conditions, may enter a slot 31 in one of the bosses of the described double crank and thus lock together the said crank and gear 24 of which arm 29 is a rigid part. The last named gear being then held against rotation serves to also look the internal gear against rotation upon its axial shaft 21 and said internal gear becomes practically fixed on said shaft and rotates with it. When used under such con-- ditions the internal gear serves to drive the cycle at the highest speed and is in efiect the same as ordinary cycles of this class. When however it is desired to bring into use an increase of power to assist in climbing grades, the bolt 30 is withdrawn from the notch 31 and the smaller gear 24 may. then be carried by the double crank around within the internal gear, the small gear being mean- 9 5 while restrained from rotating upon its own axis (the wrist pin) by means of peculiar mechanism which I will proceed to describe. This traverse movement of the smaller gear serves to impart to the internal gear 25 a 10c very much slower movement (proportionate to the relative diameters of the two gears) and increases correspondingly the propelling power produced by a given weight upon the pedals 23. I have already referred to a radial arm 29 which is secured fixedly to the small gear 24. \Vhen the end of bolt 3O is in notch 31 said arm swings (with said gear) around the shaft 21 which is then the common center around and with which both gears rotate but when it is desired to utilize the de-' scribed high power mechanism, an arm 32 with hook shaped free end is lowered into the path of the outer end of arm 29 and said arm and its connected gear are stopped; the bolt 30 being at the same instantwithdrawn from notch 31.

The arm 32 is hinged to the cycle frame and is of such length that its free (hooked) end may swing upward and downward as indicated in dotted lines in Figs. 4, 7 and 8 to meet the varying positions assumed by the small gear 24 as the latter is carried around within the internal gear. The small gear is thus restrained from revolving upon its own axis but is free to be carried by the double crank around the common center, the shaft 21, and in consequence a slow movement is imparted to the internal gear 25"and to its chain 27. The direction of movement of the gears is shown by an arrow in Fig. 6. arranged forproducing the greatest speed, the arm 32 being raised out of the path described by the free end of arm 29 and the bolt 30 being entered in notch 31.

The arm 32 is controlled by a rod 33 that extends upward within easy reach of the rider; as seen in Fig. 1. This operating rod 33 is attached to a bar 34 secured to one side of arm 32 by a screw 35 passing through a slot 36 in said bar in such manner that the bar is movable lengthwise. The free end of arm 32 is formed as a hook 37, the arm being cut away as at 38 to provide an opening of considerable length adjacent to the hook, and at theopposite end of said opening is pivoted a crank-lever or finger whose longer arm 39 may be swung upward into said opening (see Fig. 2) or may be swung outward as in Figs. 4, 6 and 7. The shorter arm of the crank-lever is pivoted to the end of the described bar 34 and a spring '40 is provided that connects said bar with the crank lever in such manner as to throw the lever arm 39 outward (see Fig. 6). When the operating rod 33 is drawn upward by the rider of the cycle, the bar 34 is first moved lengthwise as far as its slot 36 will permit it to go (thus swinging the lever 39 into the opening 38 as in Fig. 8), and continued movement of said rod 33 will then result in lifting the arm 32 away from the end of the bolt-arm 29, as in Fig. 2.

The bolt 30 is supported on the arm 29 at one end by a slotted post 41 In Fig. 2 the parts are shown as ber of teeth of the said gears.

through which it passes and at the"- other (outer) end by a slotted stud 42 having a flange or head 43. A spring 44 connects post 41 with the said bolt and acts with a constant tendency to draw the latter forward into the notch 31.

The outerend of bolt 30 is provided with two notches 45 46 the latter of which, when the bolt is forced outward, may be engaged by a dog 47 pivoted in the slot of stud 42 (see Figs. 11 and 1-2), the said dog then acting as a latch to keep the bolt from entering notch 31. The same pivot that supports the dog 47 bears upon its outer end another dog or operating arm 48, best seen in Fig. 10 which shows the reverse side of the arm 29 and its connected parts.

When the machine" is used upon level ground, and speed is desired rather than great power, the hooked arm 32 is raised out of i reach of the bolt arm 29 as in Fig. 2. 1 When however it is desired to climba steep grade, and power is desired rather than speed,

the riuer grasps theend of rod 33 and forces it downward, resulting first, in sliding bar 34 upon its pivot screw and swinging the lever arm 39 downward, away from the opening 38, and, second, in forcing the hooked arm 32 downward into the pathof the free end of the bolt supporting arm 29; When said boltsupporting arm is again brought around, the notclr 45 of the bolt 30', is engaged by the cam-shaped inner edge of lever-arm 39 (see Figs; 6 and 7) and said bolt is withdrawn from notch 31, thus disengaging the small gear 24 from the shaft 21 and preventing said small gear from further rotation upon its own axis. When the bolt 30 is withdrawn from notch- 31 the dog 47 drops into the notch 46 and then acts as a latch to prevent saidbolt from looking with its notch until again needed. Continued rotation of the pedal shaft 21 will now simply carry the small gear around within the internal gear 25 and each complete movement of the small gear around the shaft 21 will serve to move said internal gear and its chainforward a distance equal to the difference in the num If, for example, the internal gear has seventy twoteeth and the small gear forty eight teeth each complete circular movement of the latter will move the former forward one third of a revolution. gaged from the notch 31 and the high power mechanism put to work, the resistance offered by the internal gear, chain, 850., tends to rotate the small gear rearward upon its So soon as the bolt 30 is disenthe dog 48 (see Fig. 8). This serves to rock the connected dog 47 to release bolt 30, which is then left to the control of spring 44: which latter immediately draws the bolt inward. When the bossof the dou' ble crank again comes around it engages and pushes back said bolt until the notch comes 1nto coincidence with the bolt end when the latter drops into said notch. The resistance due to the meshing contact of the two gears 1s lmmediately reversed and the stud 42 leaves the hook of arm 32 and it is carried forward underneath the lever-arm 39, the latter being then in the position illustrated in Fig. 8. The rider then draws rod 33 and the connected arm 32 upward, out of the path of the bolt supporting arm 29,? and the high speed mechanism is ready for continued use.

My described difierential gearing and the mechanism for controlling the same, are quite simple and in compact form and do not require material changes in the construction of bicycles to which they may be attached.

Having described my invention, I claim- 1. In combination with an interiorly geared sprocket wheel, a smaller gear wheel mounted on a crank and in mesh therewith, a radial arm secured to the smaller wheel and provided with mechanism forlockin g said smaller wheel against rotation upon its axis, and an v arm pivotally secured to the cycle frame for engaging with said radial arm and releasing the locking mechanism, substantially as set forth.

2. In combination with an interiorly geared sprocket wheel, a smaller gear wheel mounted on a crank and in mesh therewith, a radial arm secured to the smaller wheel provided with mechanism for locking the smaller wheel against rotation upon its axis, an arm pivotally secured to thecycle frame for engaging with the end of the radial arm, a finger pivotally secured to said pivotal arm for releasing the locking mechanism and means for moving said pivoted arm and lever, substantially as set forth.

3. In combination with a sprocket-wheel having internal gear teeth a smaller gear in mesh therewith mounted upon a crank with notched boss as set forth, a radial arm 29 secured to said smaller gear, a bolt mounted to slide upon said arm and adapted to enter said notch, and mechanism, substantially as herein described, for locking and releasing said bolt.

4. In combination with an interiorly geared sprocket wheel, a smaller gear wheel mounted on a crank and in mesh therewith, a radial arm secured to the smaller wheel and provided with a locking bolt, the outer end of which bolt is provided with notches, a dog for engaging with the shoulder of one of the notches and provided with an operating arm, a lever pivotally secured to the frame of the cycle and provided with a finger for engaging with the operating arm of the dog, and meansefor operating the lever, substantially as set forth.

5. In combination with an interiorly geared sprocket wheel, a smaller gear wheel mounted on a crank and in mesh therewith, a radial arm secured to the smaller wheel and provided with means for locking said wheel against rotation upon its axis, a lever pivotally secured to the frame of the cycle, the free end of which is provided with a hook for engaging with the end of the radial arm, and a finger pivotally secured to the lever for engaging with the locking mechanism upon the radial arm, substantially as set forth.

6. In combination with an interiorly geared sprocket wheel, a smaller wheel mounted on a crank and in mesh therewith, a radial arm secured to the smaller wheel and provided with means for locking said wheel against rotation upon its axis, a lever arm pivotally secured to the cycle frame, for engaging with the end of the radial arm, a' finger pivotally secured to the lever, a slotted bar upon the lever, one end of which engages with the finger, and means for moving said bar, substantially as set forth.

JOSEPH w. PROSSER. [1, s.]

Witnesses:

ALONZO M. LUTHER, FRANK H. ALLEN. 

